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Question
In Milikan’s experiment, static electric charge on the oil drops has been obtained by shining X-rays. If the static electric charge on the oil drop is - 1.282 × 10-18C, calculate the number of electrons present on it.
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Solution
Charge on the oil drop = 1.282 ×10-18C
Charge on one electron = 1.6022 × 10-19C
∴Number of electrons present on the oil drop
`= (1.282xx10^(-18)" C")/(1.6022 xx 10^(-19)" C")`
`= 0.8001 xx 10^1`
= 8.0
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